What this website speed test measures
This website speed test sends your page to Google PageSpeed Insights, which loads it in a real Chrome browser on Google's servers and runs Lighthouse, the same audit built into Chrome DevTools. You get two kinds of data. Lab data is one controlled test on a simulated mid-range phone (or a desktop), useful for finding causes. Field data comes from the Chrome UX Report: what real visitors experienced over the last 28 days. Field data is what Google uses for rankings, so when the two disagree, trust the field numbers and use the lab report to find out why.
Core Web Vitals explained
Core Web Vitals are three numbers Google measures at the 75th percentile, meaning three out of four visits must be at least that good:
- Largest Contentful Paint (LCP): when the biggest image or text block appears. Good is 2.5 seconds or less.
- Interaction to Next Paint (INP): how quickly the page responds to taps, clicks and typing. Good is 200 milliseconds or less. It replaced First Input Delay in 2024.
- Cumulative Layout Shift (CLS): how much content jumps around while loading. Good is 0.1 or less.
A page passes when all three are in the green. Low-traffic pages often have no field data of their own, so the tool falls back to data for the whole site (the origin). If there is none at all, the lab LCP, CLS and Total Blocking Time are your best guide; TBT tracks INP closely.
How to fix the most common issues
1. Images
Oversized photos are the cause of slow LCP on most small business sites. Convert them to WebP or AVIF and resize them to the largest size they actually display; the Image Compressor does both in your browser without uploading anything. Add width and height to every image to prevent layout shift, lazy-load images below the fold, and never lazy-load the hero image.
2. Render-blocking CSS and JavaScript
Every stylesheet and script in the <head> must download before anything appears. Add defer to scripts, remove plugins the page doesn't use, and minify what remains with the Code Minifier. Chat widgets, video embeds and booking tools can usually load after the first interaction.
3. Fonts
Use one or two font families, only the weights you need, and font-display: swap so text shows immediately in a fallback font. Preload the font used in your main heading.
4. Caching and the server
A slow "document request latency" means the server takes too long to send the HTML. Page caching (a caching plugin on WordPress), a CDN and a better hosting plan fix most of it. Then give images, CSS and JS a long cache lifetime so repeat visits are instant; the .htaccess generator writes the Apache rules.
These head tags cover the biggest wins for most pages:
<link rel="preload" href="/fonts/heading.woff2" as="font" type="font/woff2" crossorigin> <img src="/img/hero.webp" width="1600" height="900" fetchpriority="high" alt="..."> <script src="/js/site.js" defer></script>
Get a reliable result
Test the pages that matter (home, top service page, contact), not just the homepage. Run each test two or three times, since lab scores move by 5 to 10 points between runs. After a fix, the lab score changes right away, while field data takes up to 28 days to catch up.
Frequently asked questions
What is a good PageSpeed score?
Google colors 90 to 100 green (good), 50 to 89 orange (needs improvement) and 0 to 49 red (poor). A mobile score in the 70s or 80s is normal for a real business site with analytics and images. Passing Core Web Vitals with real visitors matters more than chasing 100.
Why is my mobile score lower than desktop?
The mobile test simulates a mid-range phone on a slow 4G connection, with about four times less processing power than a desktop. The same JavaScript and images that load quickly on a laptop take much longer there, so mobile scores are almost always lower.
What are Core Web Vitals?
Core Web Vitals are three measurements Google uses as a page experience signal: Largest Contentful Paint (loading, good under 2.5 seconds), Interaction to Next Paint (responsiveness, good under 200 milliseconds) and Cumulative Layout Shift (visual stability, good under 0.1). They are measured from real Chrome users over the last 28 days.
Why do my scores change every time I test?
Lab tests run on shared servers, and network timing, server load, ads and third-party scripts vary from run to run. Swings of 5 to 10 points are normal. Run the test two or three times and compare the median, and treat the real-user field data as the more stable number.
Does page speed affect Google rankings?
Yes, but modestly. Core Web Vitals are part of Google's page experience signals and mostly act as a tie-breaker between pages with similarly relevant content. The bigger effect is on people: slow pages lose visitors before they load, which costs leads and sales.